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JOURNAL OP FORESTRY 



obtain the stump diameter in order to cube the butt log. The measure- 

 ment may, of course, be taken either on the stump or the log itself, but 

 in the field-notes it is convenient to record it as the diameter of the 

 stump. 



Table 3. — Twenty-inch Trees 



For recording the field data, I have found a book with a large page, 

 such as the ordinary "day book," bound in stifif boards, to be the most 

 convenient. One page is allotted to each diameter class, and one line 

 is usually enough for recording the data on one tree, so that thirty or 

 more trees can be recorded on one page. The form of notes which I 

 have found very satisfactory is illustrated in Table 3, in which is re- 

 corded the data on ten trees of the 20-inch class. In the first column 

 is the number of the tree measured, in the second (Stp.) the d. i. b. 

 of the stump. The columns headed by numerals are for the log meas- 

 urements, column I containing those for the butt log. For each tree 

 the first number in each column is the length of the log in feet and the 

 second is the top diameter in inches. The columns for length, scale, 

 and volume need not be filled out in the field, but it is convenient to 

 have such columns in the field book if there is room for them. The 

 sum of each of these columns will be, respectively, the total length, total 

 scale, and total volume for the trees of that diameter class, which totals 

 may then be transferred to their respective columns in a table similar 

 to Table 2. 



Using the same data (given in Table 2), I have drawn curves based 

 upon only a few diameter classes or diameter groups — as, for example, 

 fourth or fifth diameter class — and find that the resultant curves are 

 almost identical with the one based upon all diameters. It therefore 

 seems reasonable to assume that accurate results may be obtained from 

 the data of a comparatively small number of trees, provided a number 



